Having finally laid to rest speculation about a presidential run, Chris Christie can return to reforming his state. As the governor said yesterday, theres plenty of work left to do to “fix a broken New Jersey.”

More than a decade of fiscal mismanagement has left Jersey in such a deep hole that, even after Christies reforms, the state has one of the nations shakiest pension systems and an economy that was going nowhere even before the housing bubble burst. The Garden States business environment is toxic to investment, and its local governments are burdened by overspending and onerous state mandates.

Without Christies leadership, Trenton would have fallen into the political paralysis besetting states like California and Illinois. Even with Christie in the statehouse, the battle is far from over.

How bad is it? Last year, Christie roiled bond markets when he warned that public-worker costs would “bankrupt” the state. Thats not idle talk. For more than a decade, Jersey has artificially balanced its budget by ignoring its pension obligations, which amount to some $3 billion a year. Some state pension funds could start running out of money between 2015 and 2018.

Earlier this year, lawmakers enacted reforms requiring workers to contribute more money to the system, but the state acknowledged that it would take seven years until it could fully make its required contributions. Somehow, the state must come up with $400 million to $500 million in new revenues each year for the next seven years -- and then find even more cash to begin making up for the years of skipped pension-fund contributions.

Jersey faces this steep challenge even as we confront a possible double-dip recession and a long, slow recovery after that.

Making the road back even tougher: The state economy lagged the nations even during the boom times of the last decade, because Jerseys become one of the least business-friendly states in the country.

In a recent study of more than 10,000 new or expanded manufacturing facilities nationwide from 2007 to 2009, a California research group ranked Jersey second-worst in private-sector investments, attracting a per-capita average of just $200, compared to $1,335 nationwide.

Christie has pledged to remake the states business image by cutting regulations and reducing taxes, but hes had little time or maneuvering room to do that. Meanwhile, Jersey is so desperate for revenues that, earlier this year, financial executives surveyed by CFO magazine rated its tax environment one of the most aggressive and least fair among the states -- hardly a confidence-builder for business.

Christie points out that you cant separate the problems of states from their cities, towns and school districts. Thats certainly true of New Jersey. Its municipalities, which boast the nations highest property-tax burden, have seen state aid decline. If Trenton is to confront its pension problems, then local governments cant count on much new aid anytime soon.

The problem, as the states mayors and schools chiefs point out, is that some of their biggest costs are imposed by the state. Christie has promised to hack away at mandates that force spending on schools and towns. But he cant do anything right now about the biggest mandate -- a series of rulings by the states Supreme Court that have forced Jersey to spend as much money on its urban school districts as the states wealthiest districts spend.

That spending has not only burdened the state budget with some $4 billion more a year in costs (with no boost in student performance), but its squeezed middle-class communities because there isnt much aid left for them. The property-tax burden has rendered some towns unaffordable for many families.

Christie has promised to seek relief for towns by remaking the Supreme Court. Thats probably his biggest battle -- and he hasnt even started. He faces a monumental fight to transform it from a mechanism for social engineering into a legitimate judicial body.

The governor said he felt honored by the constant calls for him to run. But he must have known that if he jumped into the presidential fray, fiscal time-bombs would be exploding back in Jersey with some regularity. Without Christie, the states GOP -- which is nearly as responsible as the Democrats for Jerseys woes -- would have been rudderless and incapable of continuing the agenda hes laid out.